Photocomposition device

ABSTRACT

The device is a photocomposition system in which a font of transparent characters is disposed along a circular path in a plane and a light pipe is mounted for rotation with one end of the pipe on the axis of rotation and the other end positioned to trace out a path parallel to the font of characters. A periscopic system is mounted for fixed rotation with the light pipe, one end of the periscope being positioned to the side of the font opposite the light pipe, the other end being on the axis of rotation. The optical system is provided for varying the magnification of images from the axial end of the periscope, while providing continuous base line adjustment for the magnified characters.

United States Patent Gruber [451 July 25, 1972 [54] PHOTOCOMPOSITION DEVICE [72] Inventor: Frank R. Gruber, North Wilmington,

Mass.

[73] Assignee: The Imagex Corporation, Ft. Lauderdale,

Fla.

22 Filed: Sept. 2, 1970 21 Appl.No.: 68,851

FOREIGN PATENTS OR APPLlCATlONS 506,635 5/1939 Great Britain ..95/4.5 801,480 9/1958 Great Britain ..95/4.5 826,134 3/1938 Francemi; ..95/4.5

Primary Examiner-Samuel S. Matthews Assistant Examiner-Robert P. Greiner Attorney-Schiller & Pandiscio [5 7] ABSTRACT The device is a photocomposition system in which a font of transparent characters is disposed along a circular path in a plane and a light pipe is mounted for rotation with one end of the pipe on the axis of rotation and the other end positioned to trace out a path parallel to the font of characters. A periscopic system is mounted for fixed rotation with the light pipe, one end of the periscope being positioned to the side of the font opposite the light pipe, the other end being on the axis of rotation. The optical system is provided for varying the magnification of images from the axial end of the periscope, while providing continuous base line adjustment for the magnified characters.

8 Claims, 5 Drawing Figures PATENTEDJHL 25 m2 SHEET 1 BF 2 FRA/VK R. GRUBEE nvvavraa PHOTOCOMPOSITION DEVICE This invention relates to a photocomposition system, and more particularly to optomechanical apparatus for compiling lines of selected alphanumeric characters at high speed.

Of the systems used for photocomposition, those capable of setting type at high speeds typically may employ cathode ray tubes to form and display the characters, optomechanical systems being considered much slower. However, optomechanical systems are usually considerably less expensive and simpler both to maintain and operate.

It is, therefore, a principle object of the present invention to provide a simple, optomechanical photocomposition system capable of forming lines of characters at reasonably high speeds.

Other objects of the present invention are to provide a transparent matrix bearing a font of characters disposed along a circular path, and to provide such a device wherein a font of characters can simply and readily be changed. Yet other objects of the present invention are to provide a system for reading selected characters from such a font; to provide such a system usingthe light pipe in conjunction with a periscopic system fixed for rotation with the light pipe so as to direct images of the characters substantially along a single optical path.

Further objects of the present invention are to provide such a photocomposer with an optical system for varying the magnification of the images directed along the single optical path, while providing continuous base line adjustment for the magnified characters.

Yet other objects of the invention will, in part, be obvious and will, in part, appear hereinafter. These and other objects are generally achieved by providing a photocomposition system having a substantially plane matrix of alphanumeric characters distributed along a circular path, and means for reading selected characters. The latter comprises a selectively operable light source for illuminating a light pipe having one end positioned along an axis which extends perpendicularly through the center of curvature of the circular path. The other end of the pipe is positioned so that as the pipe is rotated about the axis, light traversing the pipe will illuminate characters in the circular path. Coupled to the pipe for rotation about the same axis is a periscopic system for reflecting images of characters illuminated by light from the pipe, back to the same common axis. Mounted on the same axis is an optical system for transferring the images to a line of characters with varying magnification without moving the letters from a fixed base line.

For a fuller understanding of the nature and objects of the present invention, reference should be had to the following description taken in connection with the accompanying drawings wherein:

FIG. 1 is a schematic side view, partly in section and partly in block form, of one embodiment of the present invention in which the path of light therethrough is shown in dotted lines.

FIG. 2 is a detail of FIG. 1, partly exploded and partly fragmentary, showing the character matrix;

FIG. 3 is a schematic perspective of another detail of FIG. 1 showing a magnifying and linkage system; and

FIG. 4B is a diagram illustrating the operation of the device of FIG. 3 as compared to the prior art shown in FIG. 4A.

Referring now to the drawing, there is shown a photocomposition system using a selectively triggerable flash tube 20 as a light source. Condensing lens 22 is provided for focusing light from source 20 onto one end 23 of light pipe 24. The latter typically can be a solid rod of polymethylmethacrylate, a bundle of fiber optical elements or the like, which will conduct light along a nonlinear path with substantially no attenuation.

Elongated shaft 26 is mounted for rotation about its axis AA of elongation (shown in broken line), being supported adjacent opposite ends by suitable bearings 28 and 30. End 23 of pipe 24 is mounted concentrically with an end of shaft 26 for rotation with the latter, the remainder of the pipe then being angled with respect to axis AA. The opposite end 32 of pipe 24 is bent so as to be directed parallel to axis AA and is fixed to collar 34 which is in the form of a flange mounted on shafi 26, intermediate its ends. Thus, as shaft 26 rotates, end 23 of pipe 24 remains coaxial with axis AA while end 32 traverses a circular path.

Means, such as motor 36 and belt 38 coupling motor 36 and shaft 26, are provided for rotating the latter. Mounted about shaft 26, but not rotatable therewith, is means for releasably holding in a substantially fixed relation to the path of motion of end 32, an interchangeable alphanumeric character matrix 40 which will be described in detail hereinafter. The matrix is substantially a planar element disposed perpendicularly to axis AA, so as to intercept light emitted by end 32 of the light pipe.

Mounted on shaft 26 for rotation therewith is periscopic system 42 comprising window 44 positioned to admit light directed parallel to axis AA, and emitted from end 32 of pipe 24. Behind window 44 is lens 46 for directing light from the window onto first plane mirror 48 mounted typically at an angle of 45 to axis A A. A second plane mirror 50 is mounted at an angle of 45 to and intersecting axis AA so that light from lens 46 reflected by mirror 48 is re-reflected by mirror 50 substantially along axis AA. End 52 of shaft 26 is hollow so that light from mirror 50 can exit along the shaft axis.

In the path of light exiting from periscopic system 42 is preferably a first lens system 54 for collimating the light. In the path of collimated light from system 54 is an optical system, shown generally at 56 for transferring images of the characters on matrix 40 to a line form with variable magnification while maintaining a fixed reference base line for the images, as will be explained hereinafter. An oscillating or rotating mirror 58 is disposed for projecting images formed by system 56 onto a focal surface formed by circularly curved platen 60.

Matrix 40, shown in detail in FIG. 2, preferably com rises a cruciform frame 66 having four extending arms 68. Each arm 68 has a substantially I-I-shaped cross section so that the frame defines four quadrants, each of which is bounded on two sides by a corresponding pair of mutually perpendicular channels such as 70 and 72. Releasably mounted in the channels bounding each quadrant is a respective character plate 74. Preferably plate 74 bears a line of characters 76 which are light transparent, the remainder of the plate being light opaque. The line of characters is arranged along an are such that when the plate is properly held within channels 70 and 72, the arc is substantially congruent with a segment of the path of motion of end 32 of pipe 24. Further, the letters or characters in each plate are arranged so that they are all positioned facing in the same direction on a common Cartesian coordinate system. To change a font thus simply requires that only one quadrant plate be removed and a new plate with a different type style or such be inserted. There is obviously no need to replace the entire matrix simply to change type style or characters.

Alternatively, one can use a frame divided into three or five or more equiangular segments in which corresponding removable plates may be mounted. Also, each plate may contain more than one font of characters simply by arranging each font on its own circular are having a different radius from the center at axis AA. This would then require two or more light pipes sweeping out a plurality of concentric paths. If a plate contains, however, two fonts arranged on separated arcs both having the same radius of curvature, then the fonts can be individually read according to their radial position in frame 66. Accordingly, the latter would then be modified to provide means for holding each font plate at different radial positions. It should be noted that, in any event, each font can be removed or replaced by a simple motion along a plane perpendicular to the axis AA, which can be accomplished during and without substantially interrupting the functioning of the device.

Optical system 56, shown in detail in FIG. 3, comprises a zoom-type lens system 78 of known structure having the usual adjusting lever 80 for varying the magnification provided by system 78 in known manner. System 78 itself is fixedly positioned (by means not shown) in the path of light from system 54. Lever 80 is pivotally connected to link 82 which, in turn, is pivotally connected to one arm of bell crank 84. The latter is mounted at the juncture of its arms for pivotal movement about fixedly positioned pin 86. The other arm of bell crank 84 terminates in a fork embracing pin 88. Pin 88 is fixed to slide 90. The latter is mounted in keyway 92 for movement in a plane parallel to and displaced from axis AA which extends also along the optical axis of zoom lens 78. Mounted on slide 90 in the path of light emergent from lens 78, is field lens 94.

The operation of the device can be described briefly. Flash tube 20 is triggered selectively to provide pulses of illumination. The light from tube 20 is focused by lens 22 onto end 23 of light pipe 24, end 23 preferably having a face which is optically flat, perpendicular to axis AA and parallel to a similarly optically flat face at end 32. Motor 36 causes pipe 24 to rotate so that end 32 sweeps out a circular path congruent with one or more lines of characters in matrix 40. The image of the character in matrix 40 illuminated by any flash is formed by lens 46 and transmitted to a position along axis A-- A by periscope 42 and thence by lens system 54 to optical system 56.

As lever 80 is moved to change magnification of the character image by zoom lens 78 (when and if desired), link 82 will turn ball crank 84 causing lens 94 to move laterally across the optical axis of lens 78. The linkage provided by link 82 and bell crank 84 is preferably arranged to proportion this lateral lens motion to the axial motion of lever 80 (and hence the change in magnification by lens 78) so that the projected image always remains, at least along one axis, fixed to a margin or reference line regardless of magnification. This is shown graphically in FIG. 4A where, for example, the large letter P is disposed along given X-Y axes. Reduction of the image size to the smaller letter P as shown normally appearing, moves the latter to new axes both along X and Y directions. On the other hand, as shown in FIG. 4B, the linkage of FIG. 3 insures that, for example, reduction of the letter P to the smaller size does not shift the image with respect to at least one axis, here shown as the Y axis. Of course, if one wishes to lock the image to both axes, an additional linkage and slide for field lens 94 in two orthogonal planes rather than in a single plane can readily be provided.

Field lens 94 then focuses the image provided by lens 78 onto plane mirror 58 which is rotatable preferably in increments by a stepping motor (not shown). This serves to define and separate the position of each image of a character formed along a line on platen 60.

it should be noted that about the periphery of collar 34 there is mounted a perforated ring 96 which is scanned by photocell 98 picking up light from lamp 100 transmitted by lens 102 through the perforations in ring 96. Preferably, the perforations are equally spaced from one another in a circle and there is at least one perforation corresponding radially to the radial position of each character along a given arc in a plate 74. Thus, the signals from the perforation can be used to identify (by known techniques) the position of each character relative to the position of end 32 of light pipe 24 and provide the basis whereby lamp 20 can be selectively flashed to illuminate any particular character or characters in the matrix as the shaft revolves. One of the perforations can be made larger (have a different color value, or be otherwise differentiated from the other perforations) so as to provide a zero or base position reference for synchronization of light pulses with character position. Obviously, if the angular motion of the light pipe is quite small during the flash duration (by making the latter quite short yet intense), the image motion is minimized sufficiently to avoid seriously degrading the sharpness of the image formed.

What is claimed is:

l. Aphotocom osition device including; I means for de mmg a font of characters positioned lll sequence along a substantially circular path;

a light pipe mounted for rotation with one end on an axis of rotation and coincident with the center of curvature of said path, and the second end disposed so that upon rotation of said light pipe about said axis said second end sweeps out a locus parallel to said circular path; and

a periscope coupled for rotation with said light pipe for rotation about said axis and being disposed for transferring images of said characters formed with light, from said second end of said pipe to a path colinear with said axis.

2. A device as defined in claim 1 wherein said means for defining said font includes at least one plate on which said characters aredisposed along a first circular path and means for releasably supporting said plate in a substantially stationary state so that said first path is positioned adjacent and parallel to the locus swept out by said second end of said light pipe.

3. A device as defined in claim 2 wherein said supporting means and said plate are shaped such that said plate can be released from said supporting means by motion of the plate in its own plane along a path radial to said axis of rotation.

4. A device as defined in claim 1 wherein said means for defining said font includes a plurality of equiangular segmental plates lying in substantially the same plane and arranged symmetrically about said center of curvature, each of said plates having characters disposed along a circular path at the same radius from said center of curvature, and means for supporting said plates in a substantially stationary state so that said path is positioned adjacent and parallel to the locus swept out by said second end of said pipe.

5. A device as defined in claim 1 including means in the optical path from said periscope at said axis of rotation for collimating light traversing said optical path.

6. A device as defined in claim 1 including means in the optical path from said periscope at said axis of rotation for selectively magnifying said images.

7. A device as defined in claim 6 including means for adjusting the position of a magnified image so that the latter remains tangent to a predetermined axis regardless of the extent of magnification.

8. A device as defined in claim 1 including means for determining the position of each character relative to the position of said second end of said pipe. 

1. A photocomposition device including; means for defining a font of characters positioned in sequence along a substantially circular path; a light pipe mounted for rotation with one end on an axis of rotation and coincident with the center of curvature of said path, and the second end disposed so that upon rotation of said light pipe about said axis said second end sweeps out a locus parallel to said circular path; and a periscope coupled for rotation with said light pipe for rotation about said axis and being disposed for transferring images of said characters formed with light, from said second end of said pipe to a path colinear with said axis.
 2. A device as defined in claim 1 wherein said means for defining said font includes at least one plate on which said characters are disposed along a first circular path and means for releasably supporting said plate in a substantially stationary state so that said first path is positioned adjacent and parallel to the locus swept out by said second end of said light pipe.
 3. A device as defined in claim 2 wherein said supporting means and said plate are shaped such that said plate can be released from said supporting means by motion of the plate in its own plane along a path radial to said axis of rotation.
 4. A device as defined in claim 1 wherein said means for defining said font includes a plurality of equiangular segmental plates lying in substantially the same plane and arranged symmetrically about said center of curvature, each of said plates having characters disposed along a circular path at the same radius from said center of curvature, and means for supporting said plates in a substantially stationary state so that said path is positioned adjacent and parallel to the locus swept out by said second end of said pipe.
 5. A device as defined in claim 1 including means in the optical path from said periscope at said axis of rotation for collimating light traversing said optical path.
 6. A device as defined in claim 1 including means in the optical path from said periscoPe at said axis of rotation for selectively magnifying said images.
 7. A device as defined in claim 6 including means for adjusting the position of a magnified image so that the latter remains tangent to a predetermined axis regardless of the extent of magnification.
 8. A device as defined in claim 1 including means for determining the position of each character relative to the position of said second end of said pipe. 